The current trend in the automobile manufacturing sector is to group components to obtain modular systems that simplify and facilitate their mounting by allowing to mount an assembly instead of individual elements separately.
One example of this type of modular systems is that comprised of a support or panel normally made of plastic (although it can also be metallic) in which several accessories or functional components of the door are pre-mounted, such as elements of the window lift, the lock, impact absorption systems, loudspeakers, etc.
In addition, this type of modular supports can provide a watertight seal, in which case the panel or modular support can separate a dry area (located towards the inside of the vehicle, in which the electrical and electronic components sensitive to dust and moisture are placed) from a wet area located towards the inside of the door box (in which, for example, the window lift guides are placed).
This type of panels do not incorporate the pre-mounted lining that the user will see from inside the vehicle and which provides the end finish to the door. This lining will be mounted in a later stage.
This type of door modules have been conceived to facilitate the final assembly of the product in the assembly lines and to reduce the assembly times. Therefore, the use of this type of modular support simplifies the assembly of the functional components, as these components are pre-mounted on a singe panel or modular support that can be mounted on a door frame in a single assembly stage.
European Patent application no. EP-A-1498294 describes an assembly system for a door module (with trimming) in which the window lift guides are pre-mounted, so that the lower ends of said guides are located inside the door box. To facilitate this mounting a separation is maintained between the module and the window lift rail, which is obtained by interposing a metal strip between the module and the rail. This strip is mounted on the screw used to attach the module and the rail to the door structure. The screw is pre-mounted on the module. To allow assembling the module with the pre-mounted screws, the structure or frame of the door is provided with a recess that allows assembling the module, such that the window lift rail can be placed in the inner part of the door box.
The system described in EP-A-1498294 is quite complex (it includes the aforementioned strip, screws welded to the guides, etc.) and although it may be suitable for the specific application described in said document, it may not be ideally suited to other applications.
Therefore, the need appears to exist for an attachment system that allows a simple assembly of modular supports on vehicle door frames, which is simple and comprises a small number of moving parts.